We propose to enlist 900 post-infarction subjects, under the age of 63 years, in a study designed to determine: (1) whether modification of various emotional factors comprising Type A behavior can be achieved in a significant fraction of these individuals and (2) whether such modified individuals will exhibit a statistically significant decreased incidence of recurrent myocardial infarction or sudden death. Six hundred of the 900 subjects (the experimental group) will be subject to group therapy designed to modify their Type A behavior and also encouraged to adhere to their usual regimen regarding their heart disease. The control group of 300 subjects, however, will receive only the latter type of treatment. The study will continue for at least five years.